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Date:   Mon, 26 Sep 2022 12:46:51 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Nadav Amit <nadav.amit@gmail.com>
Cc:     Thomas Gleixner <tglx@linutronix.de>, linux-kernel@vger.kernel.org,
        x86@kernel.org, Dave Hansen <dave.hansen@linux.intel.com>,
        Borislav Petkov <bp@alien8.de>, Ingo Molnar <mingo@redhat.com>,
        Nadav Amit <namit@vmware.com>,
        "Peter Zijlstra (Intel)" <peterz@infradead.org>
Subject: Re: [RFC PATCH] x86/syscalls: allow tracing of __do_sys_[syscall]
 functions
Message-ID: <20220926124651.5d35dd5f@gandalf.local.home>
In-Reply-To: <20220913135213.720368-1-namit@vmware.com>
References: <20220913135213.720368-1-namit@vmware.com>
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On Tue, 13 Sep 2022 06:52:13 -0700
Nadav Amit <nadav.amit@gmail.com> wrote:

> +++ b/include/linux/compiler_types.h
> @@ -152,8 +152,12 @@ struct ftrace_likely_data {
>   * externally visible function. This makes extern inline behave as per gnu89
>   * semantics rather than c99. This prevents multiple symbol definition errors
>   * of extern inline functions at link time.
> - * A lot of inline functions can cause havoc with function tracing.
> + *
> + * A lot of inline functions can cause havoc with function tracing. If the
> + * function is known to be safe for tracing, inline_trace can be used. Otherwise
> + * inline would prevent tracing.

Perhaps add:

 * Don't complain if this function is not available to trace!

  ;-)

-- Steve

>   */
> +#define inline_trace __inline __gnu_inline __inline_maybe_unused
>  #define inline inline __gnu_inline __inline_maybe_unused notrace
>